Method of supplying power to time-stamping device, security device, and time-correcting device

摘要

A power supply controller controls power supply to each unit included in a time-stamping device. The power supply controller determines which unit is to be supplied with power according to the length of the period when the time-stamping device is not used. However, the power supply controller continuously supplies power to an authentication key storing unit that stores an authentication key for receiving an authentic time from a time server to prevent falsification of the local time of the time-stamping device.